Devices for brewing coffee are well known in the art. Most commonly coffee extract is produced with electrically operated, percolation-type coffee makers. As heated water percolates through ground coffee, extract is produced which is isolated from the grounds via a paper or mesh filter into a container. Various machines automatically heat water, extract the coffee, filter out the coffee grounds, and collect the beverage in one self-contained device. These devices require a source of power to heat the water prior to brewing, require storage space, they can only produce a hot water coffee extract, and are comprised of a large number of parts.
U.S. Pat. No. 8,720,321B2 discloses an apparatus for cold brewing coffee featuring a middle unit, a brew chamber with self-contained filter, and an extract chamber. A cold-brewed coffee extract is obtained in the brew chamber. After the apparatus is inverted, gravity filtration of the coffee extract takes place, and the coffee extract is collected in the extract chamber. This apparatus requires a brew and extract chamber which must be manufactured as distinctly different units. The apparatus's brew chamber also requires a complex design in order to seal the filter inside it.
U.S. Pat. No. 5,028,328A discloses a coffee filter comprised of a mesh membrane supported by grids. The filters are cup-shaped and are a reusable replacement for paper coffee filters in popular drip coffee makers. Its use requires an electrically operated percolating coffee maker to be purchased by the consumer.
U.S. Pat. No. 2,885,290A discloses a coffee making device which seats to a conventional beverage cup. Hot water is poured into a receptacle containing coffee grounds and the coffee extract is filtered through filter paper directly into the beverage cup. This device does not allow the user to vary the brewing time, thus eliminating the possibility of extracting cold water brewed coffee extract due to the short contact time between the water and coffee grounds.
U.S. Pat. No. 6,561,080 discloses a brewing apparatus comprised of two self-supporting liquid containing reservoirs and a water permeable coffee grounds holder. This method for using this apparatus uses a screw-type motion to pressurize water in one reservoir and force the water through a water permeable member.